1. Field of the Invention
The present invention relates to a technique for discriminating falsification of an iris image in an iris recognition system and, more particularly, to a falsification discrimination method for an iris recognition system which makes it possible to capture an image of a pupil when changing the position of the light source in order to prevent an intrusion attempt using a photograph or dynamic image, and determine whether the iris is true or false based on the position reflected from the image.
2. Description of the Prior Art
The pupil of a human eye continues contracting and expanding. In a conventional iris recognition system, the contracted and expanded states of the pupil is detected considering such a characteristic of the eye, and, on the basis of the resulting states, falsifications in a continuous image is discriminated.
However, in order to detect the contracted and expanded states of the pupil in this manner, a series of steps of finding the position of the pupil and obtaining the radius must be performed repeatedly, so that it takes much time for detection and it is difficult to performing an accurate detection.
Reference is made to U.S. Pat. No. 4,641,349 xe2x80x9cIris Recognition systemxe2x80x9d, U.S. Pat. No. 5,291,560 xe2x80x9cBiometric Personal identification System base on Iris Analysis, and U.S. Pat. No. 5,572,596 xe2x80x9cAutomated Non-Invasive iris Recognition System and Method.
However, in these conventional iris recognition systems, they are constructed in such a manner that it is determined whether the iris is true or false based on the contracted and expanded states of the pupil. Thus, it takes much time for detection and it is difficult to performing an accurate detection. In addition, when a dynamic image in place of a photograph is illuminated continuously, the size of the pupil varies according to the time, thereby making it difficult to discriminate a falsification.
Accordingly, it is an object of the present invention to provide a falsification discrimination method for an iris recognition system which is capable of analyzing an iris image while changing the position of the light source in a system having many light sources used for a lighting apparatus, and determining whether the iris is true or false based on the reflected position.
Additional advantages, objects and features of the invention will become more apparent from the description which follows.